High-rise building is the inevitable product of urban development, and it is a production activity that invests huge resources. As a group of urban buildings, high-rise buildings have the characteristics of high floor, large volume and deep foundation. In the process of construction, there are many projects and procedures, and the requirements for continuity and safety are strict, which brings difficulties to construction technology and organization management, so scientific construction organization arrangement is particularly important.
1. Project summary
This project is a comprehensive commercial plaza in Changsha, with two 20-story symmetrical buildings, four-story podium and 1 floor basement. The south main building is a commercial and residential building, and the north main building is a commercial building. 1-4 floors are commercial buildings such as restaurants, entertainment, shopping malls, etc., 5 floors are pipeline floors, and the basement is garage and equipment floors.
2. The whole construction process control
The whole construction process belongs to the highest level of the construction process, which reflects the construction flow relationship between units (regions) in high-rise building engineering. It is the management core of high-rise building project and the key to realize the combination of economy and technology. Mastering it can carefully study and arrange the labor allocation, material construction, mechanical equipment, labor time and construction methods of the project. Be aware of it and ensure the orderly development of the project.
2. 1 construction process control
The division of construction flow section should focus on the main structure of high-rise buildings; The tower can be divided into three areas: main core area, main peripheral area and area outside the main body. The area outside the main body can be further subdivided according to the needs of the project scale and construction organization. The relationship between the tower and other areas changes with different construction stages. In the construction stage of underground structure, the tower is closely connected with other areas through the basement, and the relationship is complicated. There are many changes in flow construction methods, and different flow construction methods are adopted, and the effect is completely different. Therefore, the research on the whole process of high-rise building construction mainly focuses on the underground structure construction stage. In the construction stage of underground structure, there are three basic ways in the whole process of high-rise building construction: parallel construction, sequential construction and flowing water construction. The three methods of flowing water construction have their own advantages and disadvantages, and should be chosen reasonably according to the construction characteristics of super high-rise buildings. In order to shorten the construction period and recover the investment as soon as possible, the construction method of tower first and then flow later is adopted in this project.
2.2 Tower construction process
The working face of iron tower construction is narrow, but there are many construction procedures. There are many processes of 10 in structural engineering construction alone, and each process needs relatively independent working space and time. Therefore, the working space of tower construction is extremely precious, so it is necessary to arrange the working space reasonably in the vertical direction according to the construction characteristics of super high-rise buildings and the construction technology order to ensure the bottom-up flow construction of each process. Through reasonable arrangement of construction procedures, this project has realized orderly overlapping flow of various sub-projects, with an average construction speed of 3d// floor, and its experience is worth learning.
3. Construction progress plan
Construction progress plan is an important part of construction organization design, and it is also an important means to implement plan management in engineering construction. Construction progress plan is the time plan of project construction, which stipulates the start and end time, construction sequence and construction speed of project construction, and is an effective tool to control the construction period. There are four main types of schedule: general schedule, unit project schedule, division project schedule and resource demand plan.
3. 1 General construction schedule
The overall construction schedule is the time embodiment of various construction activities on the construction site. The preparation of the general construction schedule is to schedule all the projects on the site according to the construction scheme and the development procedure of the project in the construction deployment. Correctly compiling the general construction schedule is an important condition to ensure the timely delivery of construction projects and reduce the construction cost of super high-rise buildings.
3.2 Tower construction progress plan
The iron tower construction progress plan belongs to the unit project construction progress plan, which is compiled on the basis of the established construction plan, according to the specified construction period and various resource allocation conditions, in accordance with the reasonable construction sequence and the principle of organizing construction during construction. Use crossing diagram, network diagram or image diagram to determine the arrangement and overlapping relationship in time and space of each sub-project from construction start to tower completion.
4. The main professional construction technology and management control
4. 1 reinforcement works
4. 1 1 Binding of steel mesh between platform bottom plate and cylinder wall. The intersection of two rows of steel bars should be fastened at each point, and the middle part should be fastened every plum blossom; For the steel mesh with two-way main reinforcement, all the intersections of reinforcement should be fastened. When binding, pay attention to the formation of eight-shaped wires at adjacent binding points to avoid skew deformation of the mesh well.
Φ12 convex brace should be set between the upper and lower rows of steel bars on the floor to ensure the spacing between the two rows of steel bars. Correctly speaking, the reinforcement of the pipe body should be "∽" hoop and concrete pad. Column with lead wire concrete pad, beam slab with concrete pad to control the concrete protective layer.
4. 12 stirrups in columns or beams should be perpendicular to the main reinforcement, the stirrup corners and the fork points of longitudinal reinforcement should be fastened, and the fork points of stirrups and longitudinal reinforcement can be tied into clubs or staggered to prevent the skeleton from being skewed; Stirrup joints are vertically staggered on two vertical bars in the beam, and vertically staggered in the column at the intersection of stirrups and vertical bars at the corner of the column.
4. 13 the upper reinforcement of the cantilever plate and the outlet should be positioned correctly to prevent cracks from appearing on the surfaces of the awning plate and the cantilever plate, and the upper reinforcement of the awning plate and the cantilever plate should be supported and fixed by brackets.
4.2 template engineering
The column specification of this project is ***5, and the nine-splint angle steel frame template is adopted, and the arc beam adopts 50mm thick wooden floor and steel side plates. Other beams and platforms are made of 50mm thick planks and nine plywood, and the support system is made of multi-functional portal scaffolding.
When installing templates and supports, sufficient temporary fixing facilities must be set up to prevent overturning. The poles should be vertical, and the joints should be tightly sealed. No slurry leakage, formwork explosion and deformation are allowed.
The internal formwork of elevator shaft adopts cylindrical formwork and the derrick is fixed. When the formwork is dismantled, it will be lifted by the crown block, and the outer formwork will be shaped by a special sheet-like large formwork, and the position and section size will be controlled by the opposite bolt.
4.3 concrete engineering
4.3. 1 The superstructure of each floor is poured twice, that is, column and wall 1 time, beam and slab 1 time. There are two methods of concrete pouring: at present, the tower crane of the on-site mixing station is used, and the high-speed derrick is used for horizontal and vertical transportation; Manual handcart; Pouring point Next, use the on-site mixing station; Concrete quantitative pump; Vertical and horizontal pipes; Floor cloth machine; Dumping point
pump concrete
A. Pipeline layout: the ratio of vertical pipeline length to horizontal pipeline length should not be greater than 3: 1. The horizontal conveying pipe is conveyed upward from the fixed pump through the elbow, and the vertical conveying pipe is conveyed upward through the pipe axis. Embedded iron pieces are placed on the shaft wall every 2m, and vertical conveying pipes are fixed on the shaft. The horizontal conveying pipe is supported by φ 48× 35 steel foot hand pipe.
B, the concrete fixed pump is arranged at the discharge port VI of the mixer. When pouring, a distributor should be set up. At the setting point, a 50cm high support platform should be set up with φ 48 steel pipes and scaffolding, and the support at the platform should be strengthened.
4.4 Vertical transportation machinery and equipment
The biggest workload of vertical transportation machinery service is wood patterns, steel bars, concrete, pipes, scaffolding materials and so on. In the upper structure construction layer, interior and exterior wall materials, floors, doors and windows and other decorative materials need to be transported in the middle construction layer, and all kinds of decorative materials are mainly transported in the lower part. Therefore, each main building is equipped with a QTZ280 attached tower crane with a loom height, a wall-attached high-speed derrick passenger and cargo elevator and a passenger and cargo dual-purpose construction elevator.
Tower cranes are mainly used for structural construction, while high-speed derricks and construction elevators are mainly used for decoration construction. When the tower crane is affected by wind and snow and its own technical parameters, the high-speed derrick and construction elevator are ready to use.
Each main building is equipped with 3-4 mobile steel platforms for construction, which are used in coordination with tower cranes. After plastic cleaning, a large number of templates and accessories in the floor will be transported to the upper construction floor to continue to use under the premise of ensuring quality, so as to reduce the consumption of reusable materials, improve the utilization rate of machinery and J, and improve the site capacity.
5. Conclusion
Due to the large-scale development of high-rise buildings, new materials, new processes and new technologies are constantly emerging. The complexity of the structure increases, and the requirements for advanced decoration are high, so the requirements for technical wood management are getting higher and higher. Therefore, it is more important to do a good job in the construction organization of high-rise buildings. We should constantly sum up and improve the construction management experience so that the construction organization can really play a role in the construction of high-rise buildings.
This paper introduces the content of "construction technology and management control of high-rise buildings". Welcome to Zhong Da for more information.
For more information about project/service/procurement bidding, and to improve the winning rate, please click on the bottom of official website Customer Service for free consultation:/#/? source=bdzd